I've been reading it's good to use a PEA fuel additive in most direct injection engines like the 2.5 Camry. It helps prevent carbon buildup on the pistons and valves. They say the 2.5 Toyota engine is not a 100% direct injection engine, but it still can accumulate carbon buildup. From what I've been able to research, Gumout Multi System Tune Up is one of the better one's. As is Chevron Techron Fuel Additive. And to stay away from products like Seafoam, that are not designed for modern Ethanol based gasolines, and direct injection engines.

The stuff isn't that expensive, especially if you watch for discount coupons. If it helps prevent buildup, it's worth it. I can't see where it would hurt. What say you?